Form and Color in Nature. 253 



accumulation of minute differences which have found favor 

 in the eyes of the softer sex. Even in the human race it is 

 said that personal appearance is not wholly unconsidered at 

 the mating season. 



It is Darwin's theory that when peculiarities arise late in 

 life they are more apt to be transmitted only to the sex in 

 which they first occur. It is well known that many pecul- 

 iarities which pass from sire to son appear at a similar age in 

 each. When the male and female differ greatly, it is usually 

 the male which departs most widely from the type of the 

 family to which he belongs ; he is the most brilliantly col- 

 ored, and this peculiarity frequently is not greatly marked 

 until about the period of maturity. I wish it were possible 

 for me to give a fair statement of the evidence which has 

 been accumulated upon this point, but I must confine my- 

 self to a very few cases. It is plain that in innumerable 

 species the male exhibits himself very elaborately to the 

 female before he finds favor in her eyes, and postures like 

 a veritable coxcomb. Of the more curious cases among 

 birds, the most frequently noted is that of the bower-birds 

 of Australia. These, of which there are three species, build 

 an elaborate bower upon the ground, or sometimes raised 

 upon a platform of sticks. Their nests are formed in the 

 trees. The bowers are places of assembly for the sole pur- 

 pose of courtship. Both sexes assist in the erection, but the 

 male is the principal workman. In the fawn-breasted 

 species the bower is nearly four feet in length and eighteen 

 inches in height. " Each species decorates its bower in a 

 different manner. The satin bower-bird collects bright-col- 

 ored feathers, bleached bones, and shells ; ' these objects are 

 continually rearranged, and carried around by the birds 

 while at play.' The spotted bower-bird lines its bower with 

 tall grasses, kept in place by round stones, which are 

 brought from great distances, together with shells. The 

 regent bird makes use of bleached shells, blue, red, and 

 black berries, fresh leaves, and pink shoots, the whole 

 showing a decided taste for the beautiful ! " 



Among other birds, " the males sometimes pay their court 

 by dancing, or by fantastic antics performed either on the 

 ground or in the air." The capercailzie and blackcock, 

 which are both polygamists, have regular appointed places, 

 where during many weeks they congregate in numbers to 

 fight together and to display their charms before the females. 

 " The elder Brehm gives a curious account of the Balz, as 



